问题补充：
Great changes have taken place in that school. It is no longer it was 20 years ago, it was so poorly equipped.
AWhat; when
B. that; which
Cwhat; which
D. which; that
答案：
(答案→)A. What; when
B. that; which
C. what; which
D. which; that
解析： 考查表语从句和定语从句。It is no longer后面是表语从句，且从句缺少was的表语，要用 what引导，排除B,D；20 years ago是先行词，且定从it was so poorly equipped缺少时间状语，要用when引导。所以选A。
